title: Enhanced magneto-optical properties of semiconductor EuS nanocrystals assisted by surface plasmon resonance of gold nanoparticles.
abstract: Remarkable magneto-optical properties of a new isolator material, that is, europium sulfide nanocrystals with gold (EuS-Au nanosystem), has been demonstrated for a future photo-information technology. Attachment of gold particles that exhibit surface plasmon resonance leads to amplification of the magneto-optical properties of the EuS nanocrystals. To construct the EuS-Au nanosystems, cubic EuS and spherical Au nanocrystals have been joined by a variety of organic linkers, that is, 1,2-ethanedithiol (EDT), 1,6-hexanedithiol (HDT), 1,10-decanedithiol (DDT), 1,4-bisethanethionaphthalene (NpEDT), or 1,4-bisdecanethionaphthalene (NpDDT) . Formation of these systems was observed by XRD, TEM, and absorption spectra measurements. The magneto-optical properties of the EuS-Au nanosystem have been characterized by using Faraday rotation spectroscopy. The Faraday rotation angle of the EuS-Au nanosystem is dependent on the Au particle size and interparticle distance between EuS and Au nanocrystals. Enhancement of the Faraday rotation of EuS-Au nanosystems was observed. The spin configuration in the excited state of the EuS-Au nanosystem was also investigated using photo-assisted electron paramagnetic resonance.
authors.affiliation: Division of Materials Chemistry, Faculty School of Engineering Hokkaido University, North-13 West-8, Kita-ku, Sapporo Hokkaido 060-8628 (Japan), Fax: (+81) 11-706-7114.
authors.forename: Akira
authors.initials: A
authors.lastname: Kawashima
authors.forename: Takayuki
authors.initials: T
authors.lastname: Nakanishi
authors.forename: Tamaki
authors.initials: T
authors.lastname: Shibayama
authors.forename: Seiichi
authors.initials: S
authors.lastname: Watanabe
authors.forename: Koji
authors.initials: K
authors.lastname: Fujita
authors.forename: Katsuhisa
authors.initials: K
authors.lastname: Tanaka
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Koizumi
authors.forename: Koji
authors.initials: K
authors.lastname: Fushimi
authors.forename: Yasuchika
authors.initials: Y
authors.lastname: Hasegawa
keywords: gold; nanoparticles; semiconductors; surface plasmon resonance